<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .add{
            width: 400px;
            height: 400px;
            font-size: 30px;
            color: white;
        }
    </style>
    <script src="./lib/jquery.js"></script>
</head>
<body>
    <div class="box">你真是个天才！</div>
    <script>
        var obj = {
             fn:function(){
                $('.box').css('background','red')
                return obj
            },
            fn2:function(){
                $('.box').addClass('add')
                return obj
            },
            fn3:function(){
               $('.box').click(function(){
                  alert('总能来点惊喜')
               })
            }
        }
        obj.fn().fn2().fn3()
    </script>
</body>
</html>